1. Technical Field of the Invention
The present invention relates to a high frequency treatment device used, for example, with an endoscope for cutting open a portion of tissue of an object to be treated and/or applying a coagulating operation to a portion of tissue of an object to be treated, such as bleeding portion, by supplying high frequency (radio frequency) current to the portion.
2. Related Art
At present, various types of high frequency treatment devices have been proposed, one of which is shown by U.S. Pat. No. 5,403,311. This publication provides a high frequency treatment capable of making high frequency current flow through a bleeding portion for being stanched. This treatment device has an electrode on the tip and supplies high frequency current to the electrode made to touch a bleeding portion. Thus the flow of the current stanches the bleeding portion.
As another conventional example, Japanese Patent Laid-open publication No. 2001-170069 has disclosed a high frequency treatment device, in which the device has a gripper with electrodes. This device is handled to have a bleeding portion gripped by the gripper to which high frequency current is supplied, with the result that a portion of tissue can be cut open and a bleeding portion can be stanched.
Another conventional high frequency treatment device has been proposed Japanese Patent Laid-open publication No. 2000-70280, in which the device has a pair of distal ends of grippers with insulators thereon. In this device of which distal ends are closed to come into contact to each other with the insulators located between the grippers. Thus the insulators make conductive gripping surfaces of the grippers prevent from being directly touched with each other, so that electric short circuit between the grippers can surely be avoided when the grippers are closed.
Of the above conventional references, the high frequency treatment device typical of the device shown in U.S. Pat. No. 5,403,311 is able to simply stanch a diseased part, because it is sufficient to supply current to the electrode touched to the diseased part. This is advantageous when urgent medical treatments are required, but disadvantageous in that this device may be difficult to stop projectile bleeding due to a lack of sufficient press of the electrode onto the diseased part. That is, simply pressing the electrode onto the diseased part results in an insufficient press to blood stanching.
Further, the high frequency treatment device represented by Japanese Patent Laid-open publication No. 2001-170069 can fully press a diseased part by the gripper and, under such a grip, high frequency current is supplied to the electrodes for blood stanching. This gripping technique is very useful for stopping projectile blooding. However, to grip a portion of tissue of an object to be treated in a quick and precise manner requires surgeon's relatively complicated operations. This means that this kind of device is not suitable for urgent medical treatments.
In addition, the device proposed by Japanese Patent Laid-open publication No. 2000-70280 is still useful, because, with a diseased part pressed sufficiently by the gripper, high frequency current is made to flow through the electrodes for blood stanching. Concurrently, with jaws of the grippers made to close to each other, a side of the gripper can be pressed onto a diseased part and high frequency current is fed to the electrodes to stop bleeding easily. However, due to the fact that the insulators on the gripper are nothing to do with current flow, there are some limitations on effective positions to grip the tissue and press the gripper onto the tissue. Precisely, it is always necessary to pay attention to which part of the gripping surfaces should be used for gripping and which part of the gripper should be used for pressing.